Best 7mm mag primer

[Buffalobwana]

Replied before coffee. Post deleted due to poor reading comprehension

 

[Chas1]

Fed 215 has been good to me

+1

 

[Stokesrjsr]

I have preferred the Federal 215 GM for a long time and they are a truly a great primer. However due to uncertainty of supply I've been forced to substitute the CCI 250. But I spite of my personal bias, I can detect no discernible difference in standard deviation or precision in a 300 meter test tunnel with an Oehler 85 ballistics laboratory. Either can achieve ES of 15 and SD of 5 or less, using new Lapua Cases, Berger bullets and Vihtavuori powder. 1000 yard groups of 1/2 MOA under favorable weather conditions is achievable with either.

 

[Husky user]

I have been told that you should use mag primers if you are firing large amounts of slow burning powder.
Anything over 60 gr.,but I have fired 65gr of RL 25 with no problem.
When I used H870 @ 79gr in a 7RM I always used Mag primers!
The only primer I won't use is Rem 91/2 ,have had too many mis fires(4 out of one box 100)(long time ago)

 

[FEENIX]

I have tested the Rem 9 1/2 large rifle primer since I have 2k of them. SD/ES were less than my standard load using the WLRM. FPS was about 30fps slower though.

And have you seen the "burn flash" on the Rem 9 1/2? wow.

In order of precedence, my preference is CCI250, F215M, WLRM, and 9 1/2M. However, in my .300 WSM and .257 WBY, I was getting single-digit SDs. Sometimes you find the right combination on a different load/scenario.

 

[memtb]

As some have suggested…..it's "not written in stone" as to the best. There are so many variables, that no one can make guarantees.

But, I suspect that with enough experimentation……you can make most any primer (those designed for 7 Mag type cartridges) work quite well! Good Luck in your search for the perfect combination! memtb

 

[Jasbo]

In order of precedence, my preference is CCI250, F215M, WLRM, and 9 1/2M. However, in my .300 WSM and .257 WBY, I was getting single-digit SDs. Sometimes you find the right combination on a different load/scenario.

G'morning, Which choice yielded those WSM & WBY single digit SD's?

 

[KH_Outdoors]

I recently tested this in my 7 saum. I was using CCI250/175 EH/63.5 gr N565 with really good results but wanted to see if a primer change would make a difference. So comparing Fed210M vs CCI250 in that combination made no difference in average velocity or group size, however significantly lower ES/SD. I've read of this in mid sized cartridges before so my takeaway like most on here is that both work great and you just have to test it to see if it makes a difference for you. Seems that cases with 60-70 gr of powder can go either way between a standard vs mag.

 

[Jim’s Hunt]

I my preference is Fed 215m

 

[John6]

FWIW, I use Fed 215 in my .280 with 60 gr. of R22. It did better in accuracy and SD than the Fed 210. Curiously, they gave a little less velocity.

John

 

[jbur13]

What are you experiencing that makes you want to change from BR2? Are you using BR2's because you can't find any others to try? I get higher velocity with the CCI250's over 215M with H1000.

 

[FEENIX]

G'morning, Which choice yielded those WSM & WBY single digit SD's?

OOPS! The 9 1/2M. The original post was corrected. Thanks!

 

[Ronald W Schaefer]

I too have read or heard somewhere that the Mag primers are designed primarily for heavy charges of ball powder and a 60 gr charge was the "suggested" cutoff for reg/mag primers. Consequently, I use CC BR-2 for all cartridges less than 60 and Fed 215 for all over that. A tad arbitrary but one less thing to "wrassel" with, kind of like the ubiquitous 1000 Ft pound rule at point of impact for big game. As Forrest Gump would say, "one less thang"...

 

[memtb]

I too have read or heard somewhere that the Mag primers are designed primarily for heavy charges of ball powder and a 60 gr charge was the "suggested" cutoff for reg/mag primers. Consequently, I use CC BR-2 for all cartridges less than 60 and Fed 215 for all over that. A tad arbitrary but one less thing to "wrassel" with, kind of like the ubiquitous 1000 Ft pound rule at point of impact for big game. As Forrest Gump would say, "one less thang"...

Magnum primers can also be beneficial for complete/proper ignition if your shooting takes place in very cold conditions…..especially with ball powders! memtb